This invention relates to a boot having a hinged upper shell and a closure system therefor.
Boots used for motorcycle racing and the like have traditionally used flexible leather uppers with sufficient thickness to protect the lower leg against airborne rocks while still allowing some flexibility of movement and feel in the lower foot region. Ski boot technology, which offers potential advantages of increased protection and durability, has found limited use in motorcycle boots because of numerous unsolved problems.
To allow relatively free hinging movement of the upper shell relative to the lower vamp shell, the front and rear edges of both the upper shell and the vamp shell have been separated apart to allow the clearance for the upper shell as it moves forward and rearward. A less rigid material has been located in the front and rear clearance gaps to enclose the shell and provide protection. However, this less rigid material has not provided the same degree of protection against flying rocks. Also inadequately protected has been the wearer's shin near the knee area, which has not been covered by the motorcycle boot, and the lower shin, which has been covered but with a material which will not withstand extreme impact.
Some attempts have been made to utilize plastic parts or plastic coated parts in motorcycle boots. Entry into the boot has been restricted and uncomfortable. Plastic parts increase the difficulty of adequately waterproofing the boot and insuring a tight seal against mud and flying objects.
Closure of the upper shell, in some motorcycle boots as well as in ski boots and other sports boots, has been accomplished by overlapped side edges releasably secured by over-center buckles latched within one of several adjustment teeth. A reverse load, which causes the upper to contract, can pop the over-center buckles out of their latched position. Also, the buckles have been exposed to obstructions and could be snagged by external objects.
While ski-type boots are known which allow rocking sideways movement of an upper shell relative to a lower shell, in addition to pivoting forward and rearward movement, the hinge assembly has had externally mounted or externally accessible critical parts which thus are exposed to mud, flying pebbles, and other adverse conditions. The complexity of prior hinge assemblies has increased the possibility of maintenance problems and jamming. Prior hinge assemblies have had critical parts extending through the lower vamp shell and thus create waterproofing problems. Also, the degrees of movement between the upper and lower shells have been inadequate, or have not provided sufficient range of movement to equal or improve on leather boots.
Another problem with plastic boots is that the sole of a motorcycle boot must have some resiliency and flexibility to provide adequate grip, which characteristics are not present in a vamp shell formed of a rigid plastic material. However, the flexible sole found on traditional motorcycle boots wears quickly and greatly limits the life of the boot, and provides inadequate arch support and protection. A vamp shell of rigid plastic limits the extent to which a wearer can "feel" the motorcycle shift lever, can stand on the motorcycle peg and brake the motorcycle, and can respond to road conditions. In addition, even the rigid plastic material found in ski boots can be chewed up by the spiked motorcycle peg against which a motorcycle racer is continually placing his feet.